let a = 10;
console.time('abc')
console.log(a.toString(2))  //1010

let b = 0.1
console.log(b.toString(2))

let c = 0.2
console.log(c.toString(2))

let d = 0b1010
console.log(parseInt(d,10))

let e = 16
console.log(e.toString(16))
setTimeout(()=>{
    console.timeEnd('abc')  //输出abc:2.017s
},2000)